package main

import (
	"flag"
	"fmt"
	"os"
	"strconv"
)

var usage string = "usage: " + os.Args[0] + " <number of fibs>"

// fibonacci is a function that returns
// a function that returns an int.
// from cpython/Doc/build/html/library/functools.html
// [0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610]
func fibonacci() func() int {
	cur_fib := 0
	nxt_fib := 0
	return func() int {
		if nxt_fib == 0 {
			nxt_fib = 1
			return 0
		}
		tmp := cur_fib
		cur_fib = nxt_fib
		nxt_fib += tmp
		return cur_fib
	}
}

func main() {
	flag.Parse()
	if len(flag.Args()) != 1 {
		fmt.Fprintln(os.Stderr, usage)
		os.Exit(1)
	}
	count, err := strconv.Atoi(flag.Arg(0))
	if err != nil {
		fmt.Fprintf(os.Stderr, "%s\n", err.Error())
		os.Exit(1)
	}
	f := fibonacci()
	for i := 0; i < count; i++ {
		fmt.Println(f())
	}
}